Golf is a very fickle game, and extremely hard to dominate. Through the course of a round there are so many good and bad breaks you must contend, including weather. One will playing in the morning with calm conditions while the afternoon guys play in Doral-like conditions yesterday.
So much luck in golf involved as well....good and bad bounces....a "perfect" putt will lip out...etc. Amazing to me with so many good players that Tiger wins as often as he does.
For example, I am a little better tennis player than my friend, yet I will win practically every time as through the course of a match the better player will generally always win. I am also a little better golfer than he is, yet he will beat me 4 out of 10 times because golf is just so unpredictable. So when a tennis player builds a game that is better than everyone else, it is somewhat predictable that he will win as the better player will generally come out on top.
On the other hand, as the WGC Match Play proved, the 50th best player in golf is fully capable of beating Tiger any day of the week because of the nature of the game. Yet the 50th player in Tennis has practiclly zero chance against Federer, because the most dominate player generally will always win.
In summary, we will very likely see other Federers come along every few years and have spurts of domination, but we will probably never, ever see another Tiger come along and do what he has done due to the nature of the game. In summary, tennis is way, way easier to dominate than golf is.